US8002876B2 - Method and apparatus for electrostatically charging and separating particles that are difficult to separate - Google Patents

Method and apparatus for electrostatically charging and separating particles that are difficult to separate Download PDF

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Publication number
US8002876B2
US8002876B2 US11/794,960 US79496006A US8002876B2 US 8002876 B2 US8002876 B2 US 8002876B2 US 79496006 A US79496006 A US 79496006A US 8002876 B2 US8002876 B2 US 8002876B2
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zones
ionization
separation
zone
particles
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US11/794,960
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US20090165648A1 (en
Inventor
Werner Jakob Frank
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Wallstein Rothemuehle Sp Z OO
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Balcke Duerr GmbH
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Assigned to HOWDEN ROTHEMUEHLE GMBH reassignment HOWDEN ROTHEMUEHLE GMBH CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: BALCKE-DUERR ROTHEMUEHLE GMBH
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00—Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/02—Plant or installations having external electricity supply
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00—Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/34—Constructional details or accessories or operation thereof
    • B03C3/40—Electrode constructions
    • B03C3/45—Collecting-electrodes
    • B03C3/455—Collecting-electrodes specially adapted for heat exchange with the gas stream
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00—Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/02—Plant or installations having external electricity supply
    • B03C3/025—Combinations of electrostatic separators, e.g. in parallel or in series, stacked separators, dry-wet separator combinations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00—Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/34—Constructional details or accessories or operation thereof
    • B03C3/40—Electrode constructions
    • B03C3/45—Collecting-electrodes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C—MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00—Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/34—Constructional details or accessories or operation thereof
    • B03C3/40—Electrode constructions
    • B03C3/45—Collecting-electrodes
    • B03C3/51—Catch- space electrodes, e.g. slotted-box form

Definitions

  • the subject matter of the invention is a method and apparatus for electrostatically charging and separating particles that are difficult to separate from a gas fluid.
  • it concerns an electrostatic filter, and especially such an electrostatic filter methods or electrostatic filters which are suitable for filtering industrial waste gas.
  • electrostatic filters for dust separation in industrial waste gases which operate according to the so-called Cottrell principle and which can also be designated as electrostatic separating apparatuses
  • the changing and transport of the particles to be separated and their depositing on optionally specially formed collecting electrodes occur simultaneously in an electric field, with the particles, after sufficient accumulation or agglomeration, being removed from the collecting electrode either by mechanical vibration (dry dedusting) or by rinsing (wet dedusting).
  • dry dedusting dry dedusting
  • rinsing wet dedusting
  • an electrostatically working separator for dedusting industrial waste gases which works with a negative corona system.
  • a method is known in particular in which particles difficult to separate are removed from a gas fluid with the help of electrostatic charging and separating by means of only one high-voltage source for a high-voltage zone.
  • the particles are ionized successively and not simultaneously within the high-voltage zone and are thus separated.
  • a larger geometrical duct distance is in the ionization zone in this method and in these apparatuses than in the separating zone, as a result of which the field strength of the ionization zone is lower than the field strength of the separating zone.
  • the duct width for the ionization zone was therefore provided with a larger arrangement in the known filters than the duct width of the separating zone because it was expected that in the comparatively small charging or ionization zone the expected very high, but necessary specific current flow would lead to a relatively early occurring sparkover activity which thus would limit the electric power.
  • Air filters are also known which each work with a positive corona system and two high voltages. These air filters comprise a rectifier with two outputs for ionization and separation.
  • the field strengths in the known air filters are the same in the ionization and separation zone, but are provided with different voltage potentials. Both zones must be provided with a configuration so as to electrically insulated from each other.
  • positive discharge electrodes are provided in the known filters in the ionization zone, which electrodes produce a moderate ionization.
  • the invention is based on the object of avoiding the disadvantages of the described electrostatic filters and electrostatic filter methods and to reduce the energy input in the filtering of industrial waste gases.
  • the separator in accordance with the invention and the separating method in accordance with the invention therefore work with a negative corona system, in which a just sufficient charging of the particles is carried out in each high-voltage zone with the help of only one high-voltage source.
  • the transport of the charged particles and their separation therefore occurs at the lowest additional energy input at the oppositely polarized collecting electrodes, with the individual ducts known from conventional filters with negative corona systems remaining unchanged.
  • the efficient charging of the particles which occurs as complete as possible is performed with applied high voltage in the ionization zone, which on its part generates a field strength in the subsequent separating zone at lowest possible current which is sufficient for the transport and separation of the particles.
  • a low defined current in the separating zone ensures that a certain follow-up guidance of charge carriers to the positive collecting electrode is achieved in order to substantially prevent the repeated swirling (re-entrainment) of already separated particles.
  • FIG. 1 shows the particle separating behavior in an electrostatic filter
  • FIG. 2 shows examples of the typical electric characteristic performance of the negative electrode shapes for the ionization zone and the separation zone of the method in accordance with the invention
  • FIG. 3 shows a layout plan of a first embodiment of an individual separation duct of the separation apparatus in accordance with the invention
  • FIG. 4 shows a layout plan of a second embodiment of an individual separation duct of the separation apparatus in accordance with the invention
  • FIG. 5 shows a first embodiment of an electrostatic filter in accordance with the invention with two separating ducts and one ionization zone;
  • FIG. 6 shows a second embodiment of an electrostatic filter in accordance with the invention with three separating ducts and two ionization zones;
  • FIG. 7 shows a third embodiment of an electrostatic filter in accordance with the invention with two separating ducts with cooled collecting electrodes in the ionization zone.
  • FIG. 1 shows the particle separation behavior in an electrostatic filter.
  • the physically effective charging mechanisms i.e. the so-called surge or field charging and the diffusion charging, there is a more or less marked minimum of the particle fraction separation performance. This can clearly be seen in all illustrated curves.
  • FIG. 2 shows the amount to which the individual characteristics of the negative electrode geometries in question need to differ from each other so that the object in accordance with the invention can be achieved.
  • the characteristics on the left part of the diagram correspond to the highly current-drawing electrode shapes (Type A, B and C) for the ionization zone, whereas the characteristics shown in the right part of the diagram correspond to the low-current electrode shapes (Type D, E and F) for the separation zone.
  • FIG. 3 shows and overview of a single separation duct with the work sections of ionizing and separating. Adjacent analogous ducts are not shown.
  • a high-volume system 2 is connected to a high-voltage power source 1 , which system is provided with current-intensive discharge electrodes 6 and voltage-intensive or low-current negative electrodes 7 .
  • the discharge electrodes 6 are situated in an ionization zone 4 which is formed by the collecting electrodes grounded with reference numeral 12 .
  • the negative electrodes 7 are situated in a separation zone 5 which is also formed by the collecting electrodes 3 .
  • the entire high-voltage zone is marked with reference numeral 11 .
  • the ionizing zone 4 which is also known as ionization zone, a sufficient charging of the particles is achieved which are then separated optimally in the following separation zone 5 with strongly reduced turbulences and virtually missing electric wind.
  • a further ionization region 4 a with a separation zone 5 a can be provided downstream of the ionization zone 4 and the separation zone 5 .
  • FIG. 5 shows a schematic illustration of a horizontally arranged electrostatic filter, a so-called horizontal field.
  • Several rows of collecting electrodes 3 are provided here within a filter housing 8 with grounding 12 , which electrodes form several separation ducts 13 which on their part comprise an ionization zone 4 with the current-intensive discharge electrodes 6 and a separation zone with low-current negative electrodes 7 .
  • the embodiment shown here comprises two separation ducts 13 . Further separation ducts 13 can be connected, as is indicated with the broken lines 14 .
  • FIG. 6 shows a further embodiment of the electrostatic filter in accordance with the invention, with two ionization zones 4 and 4 a and two separation zones 5 and 5 a being arranged within the three illustrated separation ducts 13 . Furthermore, with their elliptical form the negative electrodes 7 shown in FIG. 6 have another possible geometry.
  • FIG. 7 shows a third embodiment with an ionization zone 4 , in which the collecting electrodes grounded with reference numeral 12 are arranged as hollow bodies (cooling chamber 10 ) which is flowed through by a coolant 9 .
  • This cooling helps prevent a re-ionization which is also known as back corona as a result of an extreme electric resistance of separated particles in the ionization zone 4 .

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  • Electrostatic Separation (AREA)
US11/794,960 2005-01-11 2006-01-09 Method and apparatus for electrostatically charging and separating particles that are difficult to separate Expired - Fee Related US8002876B2 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP05000380A EP1679123A1 (de) 2005-01-11 2005-01-11 Verfahren und Vorrichtung zur elektrostatischen Aufladung und Abscheidung schwierig abzuscheidender Partikel
EP05000380.5 2005-01-11
EP05000380 2005-01-11
PCT/EP2006/000106 WO2006074888A1 (de) 2005-01-11 2006-01-09 Verfahren und vorrichtung zur elektrostatischen aufladung und abscheidung schwierig abzuscheidender partikel

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US20090165648A1 US20090165648A1 (en) 2009-07-02
US8002876B2 true US8002876B2 (en) 2011-08-23

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US11/794,960 Expired - Fee Related US8002876B2 (en) 2005-01-11 2006-01-09 Method and apparatus for electrostatically charging and separating particles that are difficult to separate

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US (1) US8002876B2 (de)
EP (1) EP1679123A1 (de)
JP (1) JP2008526499A (de)
KR (1) KR101238619B1 (de)
CN (1) CN101137442A (de)
WO (1) WO2006074888A1 (de)
ZA (1) ZA200706171B (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130220128A1 (en) * 2010-10-29 2013-08-29 Zhongzhu Gu Single-region-board type high-temperature electrostatic dust collector
US20160074877A1 (en) * 2014-09-11 2016-03-17 University Of Washington Electrostatic Precipitator
US9595884B2 (en) 2014-12-18 2017-03-14 General Electric Company Sub-sea power supply and method of use

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008092073A2 (en) * 2007-01-25 2008-07-31 Ion A-Z, Llc Dielectric fluid cooled electrical capacitor and methods of making and using
US8961659B2 (en) * 2008-10-20 2015-02-24 Carrier Corporation Electrically enhanced air filtration system using rear fiber charging
KR101610854B1 (ko) * 2008-12-11 2016-04-21 삼성전자 주식회사 전기집진장치 및 그 고전압 전극
US20120192713A1 (en) * 2011-01-31 2012-08-02 Bruce Edward Scherer Electrostatic Precipitator Charging Enhancement
KR101973018B1 (ko) * 2016-11-29 2019-04-26 한국기계연구원 폭발성 배기가스 입자의 정전 제거 장치
US10399091B2 (en) 2016-01-08 2019-09-03 Korea Institute Of Machinery & Materials Electrostatic precipitation device for removing particles in explosive gases
US20210331006A1 (en) * 2020-04-22 2021-10-28 Mukundakumar Rajukumar Head-mounted Air Purifier

Citations (12)

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US1343285A (en) 1913-03-05 1920-06-15 Int Precipitation Co Means for separating suspended matter from gases
US3518462A (en) * 1967-08-21 1970-06-30 Guidance Technology Inc Fluid flow control system
US3907520A (en) * 1972-05-01 1975-09-23 A Ben Huang Electrostatic precipitating method
US4178156A (en) * 1976-07-05 1979-12-11 Metallgesellschaft Ag Process and apparatus for the collection of high-resistance dust
US4203948A (en) * 1977-08-04 1980-05-20 Niels Brundbjerg Air purifier of the regenerating type
US4225323A (en) * 1979-05-31 1980-09-30 General Electric Company Ionization effected removal of alkali composition from a hot gas
US4264343A (en) 1979-05-18 1981-04-28 Monsanto Company Electrostatic particle collecting apparatus
US5055118A (en) * 1987-05-21 1991-10-08 Matsushita Electric Industrial Co., Ltd. Dust-collecting electrode unit
US5290343A (en) * 1991-07-19 1994-03-01 Kabushiki Kaisha Toshiba Electrostatic precipitator machine for charging dust particles contained in air and capturing dust particles with coulomb force
US5302190A (en) * 1992-06-08 1994-04-12 Trion, Inc. Electrostatic air cleaner with negative polarity power and method of using same
US6004376A (en) 1996-12-06 1999-12-21 Apparatebau Rothemuhle Brandt & Kritzler Gmbh Method for the electrical charging and separation of particles that are difficult to separate from a gas flow
US6524369B1 (en) * 2001-09-10 2003-02-25 Henry V. Krigmont Multi-stage particulate matter collector

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1343285A (en) 1913-03-05 1920-06-15 Int Precipitation Co Means for separating suspended matter from gases
US3518462A (en) * 1967-08-21 1970-06-30 Guidance Technology Inc Fluid flow control system
US3907520A (en) * 1972-05-01 1975-09-23 A Ben Huang Electrostatic precipitating method
US4178156A (en) * 1976-07-05 1979-12-11 Metallgesellschaft Ag Process and apparatus for the collection of high-resistance dust
US4203948A (en) * 1977-08-04 1980-05-20 Niels Brundbjerg Air purifier of the regenerating type
US4264343A (en) 1979-05-18 1981-04-28 Monsanto Company Electrostatic particle collecting apparatus
US4225323A (en) * 1979-05-31 1980-09-30 General Electric Company Ionization effected removal of alkali composition from a hot gas
US5055118A (en) * 1987-05-21 1991-10-08 Matsushita Electric Industrial Co., Ltd. Dust-collecting electrode unit
US5290343A (en) * 1991-07-19 1994-03-01 Kabushiki Kaisha Toshiba Electrostatic precipitator machine for charging dust particles contained in air and capturing dust particles with coulomb force
US5302190A (en) * 1992-06-08 1994-04-12 Trion, Inc. Electrostatic air cleaner with negative polarity power and method of using same
US6004376A (en) 1996-12-06 1999-12-21 Apparatebau Rothemuhle Brandt & Kritzler Gmbh Method for the electrical charging and separation of particles that are difficult to separate from a gas flow
US6524369B1 (en) * 2001-09-10 2003-02-25 Henry V. Krigmont Multi-stage particulate matter collector

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130220128A1 (en) * 2010-10-29 2013-08-29 Zhongzhu Gu Single-region-board type high-temperature electrostatic dust collector
US9089849B2 (en) * 2010-10-29 2015-07-28 Nanjing Normal University Single-region-board type high-temperature electrostatic dust collector
US20160074877A1 (en) * 2014-09-11 2016-03-17 University Of Washington Electrostatic Precipitator
US9682384B2 (en) * 2014-09-11 2017-06-20 University Of Washington Electrostatic precipitator
US9595884B2 (en) 2014-12-18 2017-03-14 General Electric Company Sub-sea power supply and method of use

Also Published As

Publication number Publication date
EP1679123A1 (de) 2006-07-12
JP2008526499A (ja) 2008-07-24
KR20070095405A (ko) 2007-09-28
KR101238619B1 (ko) 2013-02-28
WO2006074888A1 (de) 2006-07-20
CN101137442A (zh) 2008-03-05
US20090165648A1 (en) 2009-07-02
ZA200706171B (en) 2008-04-30

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